Yellowroot, Xanthorhiza simplicissima
…And with a green and yellow melancholy,
She sat like Patience on a monument,
Smiling in grief…Shakespeare
Melancholy or not, October plants with green and yellow abound around us such as ginkgo, amsonia, sugar maple, larch, golden larch, hickory, Korean mountain ash and many others. Herein, we pay tribute to Xanthorhiza simplicissima, Yellowroot, which in addition to its roots, also reliably displays yellow autumn foliage. This monotypic (only one species within the genus) subshrub’ botanical name translates from ‘xantho’ for yellow and ‘rhiza’ for root. Its stems are unbranched, or most simple hence, simplicissima.
We may also allude to the prefix of the genus for Xanthe, a woman of classical mythology. She was one of the Oceanides, the numerous daughters of Oceanus and Tethys. These immortals were of the ocean beyond the Mediterranean, part of the teeming world of sea deities.
…And the Oceanides?
Do they sing together, perchance, in that diamond splendor,
That world of dawn and dew,
With eyelids twitching to tears and with eyes grown tender,
The sweet old songs they knew,
The songs of Greece?…Alfred Noyes
Etymology aside this 2-3-foot high shrub is native to damp woodlands from New York to Florida, west to Kentucky and Texas. Its bright yellow, slender, stoloniferous roots send up new shoots readily creating a low thicket in either partial shade or in full sun. Contemporary renowned plantsman, author, Michael Dirr writes of Yellowroot, “…magnificent plant for the difficult as well as normal sites…the more I see it the more I believe it has been slighted by American gardeners…”. A century earlier, then eminent plantsman, author Ernest Henry Wilson (1876-1930) wrote in his 1925, America’s Greatest Garden; The Arnold Arboretum, “…The flowers are small, purple in color and are borne in erect or spreading racemes at the end of the shoots and open before or with the unfolding of the leaves. These are pinnate, shining green and change to clear yellow in the autumn. The growth of the plant is dense and regular in height, making a fine ground cover. It has been very freely employed in the border planting in the Arboretum where it is considered the finest deciduous-leafed ground-cover…”. Our sister institution, Arnold Arboretum grows a 130-year-old large sweep of Yellowroot that each of these horticulturists evaluated ahead of their encomiums in print.
At Mount Auburn we have successfully used this as part of a native-plants replanting along-sides the steep, shaded, paths rising from Consecration Dell towards our Washington Tower. On a future visit to Mount Auburn look for our Yellowroot on upper Ivy Path and on Mound Avenue.
…The fields are reaped and shorn of their pride
But an inward verdure still crowns them;
The thistle scatters its down on the pool
And yellow leaves clothe the river-…Henry David Thoreau